Letters

February 1, 1996byJCK Magazine

COLORIMETER QUESTIONS

In the November 1995 issue of JCK I was surprised to find an article about the controversy over the Diamond Colorimeter, a product which we distribute throughout the U.S. While I realize the article was intended only to address the dialogue that the Colorimeter has generated among the gemological laboratories, I was quite disappointed that JCK didn’t present a full product performance analysis. The Colorimeter, on the market for nearly two years now, has proven to be a reliable, consistent, and accurate tool for gemologists and retailers. However, no current, daily users of the product were interviewed for your article to offer their opinions and insights into the quality of the grading of the Colorimeter.

A true test of the Colorimeter would have been to measure the color of 10 different diamonds on the Colorimeter and then anonymously submit these stones to the various labs for grading. I’m sure there would have been variances in the grades between the different laboratories, as well as with the Colorimeter. But with 10 stones you would be able to see a trend of the accuracy level of this machine that scientifically evaluates the stones (as opposed to subjective evaluations done by different people, at different times, under different environmental conditions).

Diamond color grades have not, in the past, relied heavily on technology. However, the Colorimeter is proving to be an essential tool for many gemologists. The real controversy that your article revealed is a possible bias by the laboratories themselves, who were asked to judge a product that could potentially affect their own business volume.

I would also like to make one correction in the article. While the Colorimeter has been offered at trade shows at a sale price of $6,750, the manufacturer list price for this product is $7,500.